Django Templatetag, List index out of range

Question

I got a simple templatetag which returns a random fact. When there are no facts in the database, I'm getting an exception value list index out of range. I wrapped the query set with try, except* and also checking if there is a fact in the template. You can see the code below:

fact.py

# template tag
from django import template
from facts.models import Fact
register = template.Library()


def random_fact():
    try:
        fact = Fact.objects.order_by('?')[0]
    except Fact.DoesNotExist:
        fact = None

    return {'fact': fact}
register.inclusion_tag('facts/fact.html')(random_fact)

fact.html

<!-- Random Fact Start -->
<div class="panel panel-default sidebar">
    <div class="panel-heading">
        <h3 class="panel-title">Did you know?</h3>
    </div>
    <div class="panel-body">
        {% if fact %}
            <p class="text-left">{{ fact.fact }}</p>
            <p class="text-right"><i class="fa fa-link"></i> <i><a href="{{ fact.website }}" target="_blank">{{ fact.author }}</a></i></p>
        {% else %}
            <p class="text-left">There are currently no studying tips!</p>
        {% endif %}
    </div>
</div>
<!-- Random Fact End -->

Answer 1

Try this:

def random_fact():
    fact = Fact.objects.order_by('?').first()
    return {'fact': fact}

Answer 2

Fact.objects.order_by('?') expression doesn't throw DoesNotExist in case of nothing found - it becomes an empty list. Getting 0-th item on an empty list throws IndexError, catch it:

def random_fact():
    try:
        fact = Fact.objects.order_by('?')[0]
    except IndexError:
        fact = None